Precision machined carbide balls and valve seats1&period; High strength&comma; high wear resistance&comma; high precision&comma; good temperature resistance and good corrosion resistance&period;2&period; Mainly used for the sealing of valves of oil pumps in petroleum industry's containing wells&comma; viscous oil wells&comma; sea oil wells and high pressure sulfur resistant oil wells&comma; etc&period;3&period; Balls and seats are used with compatible cemented carbide valve seats&period;4&period; The finished surface&comma; tolerance standard have reached the standards of the machine industry&colon; G5&comma; G10&comma; G16&comma; G40 and G100 of JB&sol;T 9145-1999&period;5&period; Precision machined cemented carbide balls of other grades and specifications are also available based on customers&grave; demands&period;6&period; Compatible high precision valve seats can also be made&period;